This project seeks to examine the interaction of cholesterol with other lipids, including glycero- and sphingolipids, and cerebrosides. Synthetic analogs of natural lipids are synthesized and used in membrane studies. It is essential to obtain full characterization of the lipids synthesized. FAB-MS, FAB-CAD-MS/MS and HR-FAB-CAD-MS/MS were all used to characterize more than 60 compounds.